asRetrieveAndGenerateSourceConfig
Casts this EvaluationPrecomputedRagSourceConfig as a RetrieveAndGenerateSourceConfig and retrieves its aws.sdk.kotlin.services.bedrock.model.EvaluationPrecomputedRetrieveAndGenerateSourceConfig value. Throws an exception if the EvaluationPrecomputedRagSourceConfig is not a RetrieveAndGenerateSourceConfig.